The primary objective of this proposal is to clone fragments of the B. subtilis chromosome harboring genes essential to sporulation and to use the resulting sporulation plasmids for three classes of experiments. First, plasmids harboring specific spore genes will be used as hybridization probes to analyze transcription of specific spore genes by an in vivo approach. Second, "spore gene" DNA from the plasmids will be used as template to identify, by in vitro methods, RNA polymerase activities that recognize and transcribe specific spore genes. Third, a plasmid will be used to analyze the previous suggestion that the spoOF cistron codes for a component of the membrane associated enzyme pppAppp synthetase. The secondary objective of this proposal is to characterize sporulation converting phages for B. subtilis and to attempt to identify the biochemical basis for conversion mediated by these phages.